Syrian state television says twin explosions at security compounds in northern Syria Friday killed at least 28 people and wounded 235 others as a government crackdown on opposition protests spiked nationwide.

The blasts targeted a military intelligence building and a security force base in Syria's northern city of Aleppo, which had been relatively quiet since the uprising against President Bashar al-Assad's regime erupted in March.

Television reports showed images of government buildings in central Aleppo with windows blown out and rubble strewn in the streets. It said that there were two blasts, one targeting a “military security” branch and a second targeting the “state security brigade” headquarters.

The reports are blaming armed terrorists for the attacks, showing live footage of mangled, bloodied bodies on the pavement outside the shattered buildings.

But rebel Colonel Riyadh al-Asaad, who heads the loosely-knit Free Syrian Army that is fighting government forces, denied responsibility for the blasts and accused the government.

The colonel said the Free Syrian Army had led an attack on the government buildings before the explosions, but had withdrawn by the time the bombs went off.

An opposition activist in Aleppo told Alhurra TV that he thinks the blasts were the work of Syria's secret police. He claims the police blamed the Free Syrian Army by calling a French television station to say the rebels were behind the bombings.

In an interview with VOA's Kurdish Service, human rights activist, Mahmoud Hamdush, said from near Aleppo that government forces are blocking roads in and out of the city center to prevent people from traveling to Aleppo's suburbs where large protests are being held against the government.

Homs remains under siege

In Syria's third largest city, Homs, witnesses say heavy shelling targeted the Baba Amr district for a seventh day. Opposition videos showed the bodies of several children they say were killed by government shells.

One witness in the outskirts of Homs says security forces opened fire on worshippers leaving a mosque, and that several people are reported to be injured.

The activist told says that despite a relentless government assaults, rebels plans no surrender.

"I am, as an activist, being pursued after they issued a ruling to execute me immediately if I am arrested," said the man, who asked for anonymity and was interviewed via Skype. "Our colleagues are advising us not to turn ourselves in because the ruling stipulates that we will be executed."

Because of restrictions on reporting in Syria, VOA cannot confirm government or opposition reports.

The activist said supplies and food are running short in the Homs region.

"We are sharing whatever available from food and the humanitarian situation is so miserable that it can’t be described," he said. "While as youth we can manage, the kids and the elders cannot bear severe hunger. There [are] no medical supplies or milk for the kids and some bakers stopped making bread due to the shortage of wheat."

Another activist in Homs said that government attacks are not letting up and that even walking one block can be deadly.

"Every day is worse than the day before," he said of the assault, "more deaths, more injured, more destroyed buildings." He said hospitals are overflowing with the wounded.

Activists say hundreds of people have died since the offensive in Homs began early Saturday.

"Homs is becoming a ghost city," one of the activists told VOA on Friday. "No one is walking in the streets... Our situation is miserable."

Attacks nationwide

Opposition activists in Damascus also report heavy government shelling in the outer suburbs and a fire at a hospital in Douma. Other reports tell of government attacks in several locations nationwide.

At a Damascus mosque, a cleric appointed with government backing claimed in a Friday prayer sermon that "outside forces" were responsible for sowing chaos and death in Syria.

Sheikh Ahmed Saleh said that money coming in from outside Syria is sowing chaos. He said government opponents do not want reform, but are trying to destroy Syria.

Syria analyst Nadim Shehadi of Chatham House in Britain says the Syrian government is stepping up its military onslaught to show that the protest movement is not peaceful.

"What the government is trying to do is convey the message that Syria is going into a civil war and that this is no longer a non-violent or peaceful protest against the government, and that this will certainly frighten any outsiders from intervening and will convey the image of another Iraq," he said.

Sectarian divisions have been rising as killings have increased on both sides of the conflict. Pro-government forces are led by members of President Bashar al-Assad's Shi'ite Alawite minority. Syrian authorities have blamed what it calls "armed terrorists" for the revolt, and said they are responsible for several sectarian attacks in recent days.

Saudi response

Early Friday, Saudi Arabia's King Abdullah criticized the United Nations for failing to pass a resolution against Syria's crackdown on protests. Speaking on Saudi television, he said "there is no doubt that the confidence of the United Nations has been shaken."

China, which joined Russia in vetoing the U.N. resolution, said it wants to maintain contact with Syrian activists after an opposition delegation visited Beijing last week. Moscow, a staunch ally of Damascus, has insisted any solution to end the bloodshed must come from within Syria.

The 22-member league withdrew its monitors in late January to protest the Syrian government's continued crackdown on protesters calling for an end to Assad's 11-year autocratic rule. The observer mission had begun in December as part of an agreement with Damascus to halt the violence.

Arab League foreign ministers are due to meet in Cairo Sunday to discuss a new plan to send a joint U.N.-Arab League observer mission to Syria.

President Assad has pledged to assign his deputy to hold a dialogue with the opposition, but such groups have rejected talks with the government.

Turkey says its government is ready to host an international conference to support the Syrian people, either in Istanbul or another regional country. Foreign Minister Ahmet Davutoglu is in Washington to meet U.S. congressional leaders and Secretary of State Hillary Clinton for talks likely to focus on Syria.

Washington has been exploring the possibility of providing humanitarian aid to Syrians in cooperation with U.S. allies. Western powers and Arab nations have said repeatedly they do not want to intervene militarily in the conflict.

U.S. Secretary of State John Kerry has told his Russian counterpart, Sergei Lavrov, that his country could face further consequences to what he called its “already strained economy” if Moscow does not fully comply with a cease-fire in Ukraine. The two met, on Monday, on the sidelines of a U.N. Human Rights Council meeting in Geneva, where Kerry outlined human rights violations in Russian-annexed Crimea and eastern Ukraine. VOA State Department correspondent Pam Dockins reports from Geneva.

Video

U.S. Secretary of State John Kerry has told his Russian counterpart, Sergei Lavrov, that his country could face further consequences to what he called its “already strained economy” if Moscow does not fully comply with a cease-fire in Ukraine. The two met, on Monday, on the sidelines of a U.N. Human Rights Council meeting in Geneva, where Kerry outlined human rights violations in Russian-annexed Crimea and eastern Ukraine. VOA State Department correspondent Pam Dockins reports from Geneva.

Video

Diagnosing infections such as HIV requires expensive clinical tests, making the procedure too costly for many poor patients or those living in remote areas. But a new technology called lab-on-a-chip may make the tests more accessible to many. VOA’s George Putic reports.

Video

Afghan officials have expressed concern over reports of a crackdown on Afghan refugees in Pakistan following the Peshawar school attack in December. Reports of mass arrests and police harassment coupled with fear of an uncertain future are making life difficult for a population that fled its homeland to escape war. VOA’s Ayesha Tanzeem reports from Islamabad.

Video

Despite the ongoing ceasefire in Ukraine, soldiers in the city of Mariupol fear that pro-Russian separatists may be getting ready to attack. The separatists must take or encircle the city if they wish to gain land access to Crimea, which was annexed by Russia early last year. But Ukrainian forces, many of them volunteers, say they are determined to defend it. Patrick Wells reports from Mariupol.

Video

As low oil prices and Western sanctions force Russia's economy into recession, thousands of Moscow restaurants are expected to close their doors. Restaurant owners face rents tied to foreign currency, while rising food prices mean Russians are spending less when they dine out. One entrepreneur in Moscow has started a dinner kit delivery service for those who want to cook at home to save money but not skimp on quality. VOA's Daniel Schearf reports.

Video

The United States and Cuba say they have made progress in the second round of talks on restoring diplomatic relations more than 50 years after breaking off ties. Delegations from both sides met in Washington on Friday to work on opening embassies in Havana and Washington and iron out key obstacles to historic change. VOA’s Mary Alice Salinas reports from the State Department.

Video

One after another, presumptive Republican presidential contenders auditioned for conservative support this week at the Conservative Political Action Conference held outside Washington. The rhetoric was tough as a large field of potential candidates tried to woo conservative support with red-meat attacks on President Barack Obama and Democrats in Congress. VOA Political Columnist Jim Malone takes a look.

Video

New Yorkers take pride in setting world trends — in fashion, the arts and fine dining. The city’s famous biannual Restaurant Week plays a significant role in a booming tourism industry that sustains 359,000 jobs and generates $61 billion in yearly revenue. VOA's Ramon Taylor reports.

Video

Issues like the Keystone XL pipeline, fracking and instability in the Middle East are driving debate in the U.S. about making America energy independent. Recently, the American Energy Innovation Council urged Congress and the White House to make expanded energy research a priority. One beneficiary of increased energy spending would be the Brookhaven National Lab, where clean, renewable, efficient energy is the goal. VOA's Bernard Shusman reports.

Video

There has been a surge of interest in the American civil rights movement of the 1950s and '60s, thanks in part to the Hollywood motion picture "Selma." Five decades later, communities in the South are embracing the dark chapters of their past with hopes of luring tourism dollars. VOA's Chris Simkins reports.

Video

With the end of summer in the Southern hemisphere, the Antarctic research season is over. Scientists from Northern Illinois University are back in their laboratory after a 3-month expedition on the Ross Ice Shelf, the world’s largest floating ice sheet. As VOA’s Rosanne Skirble reports, they hope to find clues to explain the dynamics of the rapidly melting ice and its impact on sea level rise.

Video

A Lao dam project on a section of the Mekong River is drawing opposition from local fishermen, international environmental groups and neighboring countries. VOA's Say Mony visited the region to investigate the concerns. Colin Lovett narrates.